Headrest adjustment mechanism for vehicle seats

ABSTRACT

A bushing allows for adjustability of a position of a headrest. The bushing includes a head portion having an opening and a passageway opening. The bushing also includes a body portion defining an internal passageway. The passageway opening of the head portion is aligned with the internal passageway of the body portion. The body portion includes a wall surrounding an area of reduced thickness, and a protrusion is located on an internal surface of the area of reduced thickness. The bushing also includes a moveable portion received in the opening of the head portion. The moveable portion is moveable between a first position where a feature engages a notch of a post receivable in the internal passageway of the body portion and the passageway opening of the head portion to retain the headrest in a position and a second position where the feature is disengaged from the notch of the post, allowing the post and the headrest to move relative to the bushing.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/948,215 filed on Jul. 23, 2013, which claims priority to U.S.Provisional Application No. 61/675,048 filed on Jul. 24, 2012.

BACKGROUND OF THE INVENTION

A vehicle seat can include an adjustable headrest mounted to a backrestof the vehicle seat. The headrest can be moved in a generally verticaldirection relative to the seat. Two posts are mounted to the headrest.Two guide sleeves are located within the backrest of the vehicle seat,and a bushing is received in each of the two guide sleeves. Each post isreceivable in one of the two guide sleeves.

Each post includes a plurality of notches. One bushing includes amechanism that is received in one of the notches, securing the post andthe attached headrest in a position. When the headrest is to be moved toanother position relative to the backrest of the vehicle seat, themechanism of the bushing is removed from the notch of the post, allowingthe post, and therefore the attached headrest, to slide in the generallyvertical direction relative to the backrest of the vehicle seat to adesired position. Once the headrest is in the desired position, themechanism is released to allow the mechanism to engage another notch ofthe post, securing the headrest in the desired position.

SUMMARY OF THE INVENTION

A bushing allows for adjustability of a position of a headrest. Thebushing includes a head portion having an opening and a passagewayopening. The bushing also includes a body portion defining an internalpassageway. The passageway opening of the head portion is aligned withthe internal passageway of the body portion. The body portion includes awall surrounding an area of reduced thickness, and a protrusion islocated on an internal surface of the area of reduced thickness. Thebushing also includes a moveable portion received in the opening of thehead portion. The moveable portion is moveable between a first positionwhere a feature engages a notch of a post receivable in the internalpassageway of the body portion and the passageway opening of the headportion to retain the headrest in a position and a second position wherethe feature is disengaged from the notch of the post, allowing the postand the headrest to move relative to the bushing.

A headrest assembly includes a headrest, two posts secured to theheadrest, where at least one of the two posts includes a plurality ofnotches, and a bushing to allow adjustability of a position of theheadrest. The bushing includes a head portion having an opening and apassageway opening. The bushing also includes a body portion defining aninternal passageway, where the passageway opening of the head portion isaligned with the internal passageway of the body portion. The bodyportion includes a wall surrounding two areas having a reduced thicknesson opposing sides of the body portion, and a protrusion is located on aninternal surface of each of the two areas of reduced thickness. A firstdistance is defined between the internal surfaces of the two areas ofreduced thickness, a second distance is defined between the twoprojections, and the second distance is less than the first distance.One of the two posts with the plurality of notches is received in theinternal passageway of the body portion and the passageway opening ofthe head portion of the bushing and has a third diameter that is greaterthan the second distance defined between the two projections. Thebushing also includes a moveable portion received in the opening of thehead portion. The moveable portion is moveable between a first positionwhere a feature engages one of the plurality of notches of the postreceivable in the internal passageway of the body portion and thepassageway opening of the head portion of the bushing to retain theheadrest in a position and a second position where the feature isdisengaged from the one of the plurality of notches of the post,allowing the post and the headrest to move relative to the bushing.

These and other features of the present invention can be best understoodfrom the following specification and drawings, the following of which isa brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a vehicle seat and a headrestadjustment mechanism;

FIG. 2 illustrates a view of a top portion of a backrest of a vehicleseat, the headrest, and an adjustment mechanism;

FIG. 3 illustrates a perspective view of a bushing;

FIG. 4 illustrates a cross sectional view of a moveable portion receivedwithin an opening of a head portion of the bushing when a metal pieceengages a notch in a post to retain the headrest in a first position;

FIG. 5 illustrates a cross sectional view of the moveable portionreceived within the opening of the head portion of the bushing when themetal piece does not engage the notch in the post to allow the post andthe headrest to move relative to the backrest;

FIG. 6 illustrates another perspective view of the bushing;

FIG. 7 illustrates a side view of the moveable portion;

FIG. 8 illustrates a front view of the moveable portion;

FIG. 9 illustrates a front view of the bushing;

FIG. 10 illustrates a cross-sectional view of the body portion of thebushing including areas having a reduced thickness and projections onthe internal surface of the areas having a reduced thickness; and

FIG. 11 illustrates a top view of the bushing showing the projections onthe internal surface of the areas having a reduced thickness.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a vehicle seat 10 includes a seat 12 and a backrest14. The vehicle seat 10 includes a headrest 16 that is movable in agenerally vertical direction (along an axis Z) relative to the backrest14. At least one post 18 is secured to the headrest 16. In one example,the vehicle seat 10 includes two posts 18. One of the posts 18 includesa plurality of notches 42, as explained below. The post 18 has adiameter C.

FIG. 2 illustrates a top portion of the backrest 14 of the vehicle seat10. A guide sleeve 20 corresponding to each post 18 is received withinthe backrest 14. In one example, the guide sleeve 20 is made of metal.In one example, there are two guide sleeves 20. A bushing 22 a and 22 bis received in each of the guide sleeves 20. In one example, the bushing22 a is a master bushing, and the bushing 22 b is a slave bushing. Thatis, the master bushing is actuated to allow movement of the headrest 16relative to the backrest 14 of the vehicle seat 10. As explained below,a mechanism of the bushing 22 a is manually actuated to allow the post18, and therefore the headrest 16, to move relative to the backrest 14.

FIG. 3 illustrates the bushing 22 a. In one example, the bushing 22 a ismade of molded plastic. The bushing 22 a includes a body portion 24 thatis received inside one of the guide sleeves 20. The body portion 24includes an internal passageway 26 that extends along the axis Z. Thebody portion 24 also includes a resilient feature 40 that is received inan opening (not shown) in the guide sleeve 20. When the body portion 24is inserted into the guide sleeve 20, the resilient feature 40 iscompressed inwardly to allow the body portion 24 to slide within to theguide sleeve 20. However, once the resilient feature 40 is aligned withthe opening, the resilient feature 40 is biased outwardly into theopening to retain the body portion 24 within the guide sleeve 20.

The bushing 22 a also includes a head portion 28 that defines a space 30accessible through an opening 32 on a first side 34 of the head portion28. The head portion 28 also includes a wall 36 (shown in FIG. 4) on asecond side 38 of the head portion 28. The head portion 28 also includespassageway opening 44 aligned with the internal passageway 26 of thebody portion 24. In one example, the body portion 24 and the headportion 28 are integrally formed into a single component.

FIGS. 4 and 5 illustrate a moveable portion 46 received in the space 30of the head portion 28. In one example, the head portion 28 is formed ofmolded plastic. The moveable portion 46 includes a manual contactsurface 48, an opposing spring surface 50 and a passage 52 that isalignable with the passageway 26 of the body portion 24 and thepassageway openings 44 of the head portion 28. A metal piece 54, such asa steel sheet, is molded into or snap fit in the moveable portion 46. Inone example, the metal piece 54 is a metal plate. A resilient member 56is located between the wall 36 of the head portion 28 and the springsurface 50 of the moveable portion 46. In one example, the resilientmember 56 is a coil spring. The metal piece 54 and the resilient spring56 are two separate components that are non-integral.

As shown in FIG. 4, when the moveable portion 46 is in a first position,the resilient member 56 biases the moveable portion 46 in a direction Xto a first position such that a portion of the metal piece 54 isreceived within a notch 42 of the post 18 that is received in thepassageway openings 44 of the head portion 28, the passage 52 of themoveable portion 46, and the passageway 26 of the body portion 24.Engagement of the metal piece 54 in the notch 42 of the post 18 securesthe post 18, and therefore the headrest 16, in a position.

As shown in FIG. 5, when pressure is applied on the manual contactsurface 48 of the moveable portion 46 (for example, by a finger of aperson), the moveable portion 46 moves in the direction Y to a secondposition and compresses the resilient member 56. When the moveableportion 46 is in the second position, the metal piece 54 is not receivedin a notch 42 in the post 18, allowing the post 18, and therefore theheadrest 16, to move axially along the axis Z relative to the backrest14 and the bushing 22 a.

When the pressure is released from the manual contact surface 48 of themoveable portion 46, the resilient member 56 biases the moveable portion46 back to the first position, as shown in FIG. 4. The metal piece 54engages another notch 42 of the post 18, securing the post 18, andtherefore the headrest 16, in another position.

As shown in FIG. 6, the moveable portion 46 includes a flexibleprojection 58 (shown in FIGS. 7 and 8) that is received in an opening 60in the head portion 28 when the moveable portion 46 is received in thespace 30 of the head portion 28. The flexible projection 58 retains themoveable portion 46 within the opening 60 of the head portion 28. As themoveable portion 46 moves between the first position and the secondposition, the flexible projection 58 moves within the opening 60 of thehead portion 28 to removeably retain the moveable portion 46 inside thehead portion 28.

As shown in FIG. 9, the bushing 22 a also includes a collar 62 locatedbetween the body portion 24 and the head portion 28. The collar 62includes an opening 64 having a flat bottom surface 66 and a curvedupper surface 68. A flexible wall 70 is defined between the flat bottomsurface 66 of the opening 64 and a lower surface 72 of the collar 62. Arib 74 projects from the lower surface 72 of the collar 62 (FIG. 2).When the bushing 22 a is positioned in the guide sleeve 20, the flexiblewall 70 and the rib 74 are deformable and contact an upper surface ofthe guide sleeve 20 to absorb impact.

As shown in FIG. 10, the body portion 24 includes an area 76 having areduced wall thickness. That is, a thickness of the area 76 is less thana thickness of the surrounding wall of the body portion 24 of thebushing 22. In one example, the area 76 is substantially rectangular. Inone example, the area 76 is recessed from an external side of the bodyportion 24. That is, an inner surface of the body portion 24 does notinclude any recessed portion as part of the area 76 and is substantiallysmooth in this area. In one example, the body portion 24 includes twoareas 76 on opposing sides of the body portion 24. The area 76 iscontinuous with the surrounding wall of the body portion 24, and thereare no spaces or gaps between the area 76 and the surrounding wall ofthe body portion 24. In one example, the area 76 is located between thecollar 62 and the resilient feature 40. As the area 76 has a thicknessless than the thickness of the surrounding material of the body portion24, it is more flexible.

The body portion 24 includes an elongated rib 78 located on an innersurface of the passageway 26 of the body portion 24 and aligned with thearea 76 having a reduced wall thickness. The elongated rib 78 extendsalong the X axis. In one example, there are two elongated ribs 78 eachaligned with one of the two areas 76 of reduced wall thickness. In oneexample, each elongated rib 78 is located across from the otherelongated rib 78. A diameter of the passageway 26 of the body portion 24has a diameter A, and a distance between the two elongated ribs 78 is adistance B. The distance B is less than the distance A. Additionally,the diameter C of the post 18 is slightly greater than the distance Bbetween the elongated ribs 78.

When the post 18 is received in the passageway 26 of the body portion 24of the bushing 22 a, the larger diameter post 18 presses on theelongated ribs 78 as the distance B between the elongated ribs 78 isless than the diameter C of the post 18. As the area 76 has a reducedwall thickness, the area 76 can flex when the larger diameter post 18 islocated between the smaller distance elongated ribs 78. As the post 18is moved within the passageway 26 of the body portion 24, the post 18continues to press on the elongated ribs 78, providing friction whichallows for better control of the movement of the post 18 when the post18 is being moved to adjust a location of the headrest 16. The contactalso decreases buzz, squeak and rattle of the mechanism.

When the headrest 16 is to be moved along the Z axis to anotherposition, the manual contact surface 48 of the moveable portion 46 ispressed, removing the metal piece 54 from one of the notches 42 in thepost 18. This allows the post 18, and the attached headrest 18, to moveto a desired position along the axis Z. Once the headrest 16 is in thedesired position, the manual contact surface 48 is released, and theresilient member 56 biases the moveable portion 46 into another notch 42of the post 18, securing the headrest 16 in a new position.

The foregoing description is only exemplary of the principles of theinvention. Many modifications and variations are possible in light ofthe above teachings, for instance, the inlet vanes may also haveintermediate positions. It is, therefore, to be understood that withinthe scope of the appended claims, the invention may be practicedotherwise than using the example embodiments which have beenspecifically described. For that reason the following claims should bestudied to determine the true scope and content of this invention.

What is claimed is:
 1. A bushing to allow adjustability of a position ofa headrest, the bushing comprising: a head portion having an opening anda passageway opening; a body portion defining an internal passageway,wherein the passageway opening of the head portion is aligned with theinternal passageway of the body portion, the body portion includes awall surrounding an area of reduced thickness, and a protrusion islocated on an internal surface of the area of reduced thickness; and amoveable portion received in the opening of the head portion, whereinthe moveable portion is moveable between a first position wherein afeature engages a notch of a post receivable in the internal passagewayof the body portion and the passageway opening of the head portion toretain the headrest in a position, and a second position wherein thefeature is disengaged from the notch of the post, allowing the post andthe headrest to move relative to the bushing.
 2. The bushing as recitedin claim 1 wherein the body portion includes two areas of reducedthickness and two protrusions, wherein one of the two areas of reducedthickness and one of the two protrusions and the other of the two areasof reduced thickness and other of the two protrusions are located acrossfrom each other, a first distance is defined between the internalsurfaces of the two areas of reduced thickness, a second distance isdefined between the two projections, and the second distance is lessthan the first distance.
 3. The bushing as recited in claim 1 whereinthe head portion and the body portion are integral and made of moldedplastic.
 4. The bushing as recited in claim 1 wherein the head portionincludes a first side and a second side, wherein the opening is locatedat the first side and a wall is located near the second side.
 5. Thebushing as recited in claim 4 including a resilient member locatedbetween the moveable portion and the wall of the head portion.
 6. Thebushing as recited in claim 5 wherein the resilient member is a coilspring.
 7. The bushing as recited in claim 5 wherein the resilientmember biases the moveable portion to the first position, and manualpressure moves the moveable portion to the second position against thebias of the resilient member.
 8. The bushing as recited in claim 1wherein the feature that engages the notch of the post is a metal piece.9. The bushing as recited in claim 8 wherein the metal piece is moldedinto the moveable portion or snap fit into an opening in the moveableportion.
 10. The bushing as recited in claim 8 wherein a resilientmember biases the moveable portion to the first position, manualpressure moves the moveable portion to the second position against thebias of the resilient member, and the resilient member and the metalportion are separate components.
 11. The bushing as recited in claim 1wherein the head portion includes an aperture and the moveable portionincludes a projection that is received in the aperture to removeablyretain the moveable portion in the head portion as the moveable portionmoves relative to the head portion.
 12. The bushing as recited in claim1 wherein the protrusion is elongated and extends along a substantiallyvertical axis.
 13. A headrest assembly comprising: a headrest; two postssecured to the headrest, wherein at least one of the two posts includesa plurality of notches; and a bushing to allow adjustability of aposition of the headrest, the bushing including: a head portion havingan opening and a passageway opening, a body portion defining an internalpassageway, wherein the passageway opening of the head portion isaligned with the internal passageway of the body portion, the bodyportion includes a wall surrounding two areas of reduced thickness onopposing sides of the body portion, a protrusion is located on aninternal surface of each of the two areas of reduced thickness, a firstdistance is defined between the internal surfaces of the two areas ofreduced thickness, a second distance is defined between the twoprojections, the second distance is less than the first distance, andone of the two posts with the plurality of notches is received in theinternal passageway of the body portion and the passageway opening ofthe head portion of the bushing and has a third diameter that is greaterthan the second distance defined between the two projections, and amoveable portion received in the opening of the head portion, whereinthe moveable portion is moveable between a first position wherein afeature engages one of the plurality of notches of the post receivablein the internal passageway of the body portion and the passagewayopening of the head portion of the bushing to retain the headrest in aposition, and a second position wherein the feature is disengaged fromthe one of the plurality of notches of the post, allowing the post andthe headrest to move relative to the bushing.
 14. The headrest assemblyas recited in claim 13 wherein the head portion and the body portion areintegral and made of molded plastic.
 15. The headrest assembly asrecited in claim 13 wherein the head portion includes a first side and asecond side, wherein the opening is located at the first side and a wallis located near the second side.
 16. The headrest assembly as recited inclaim 15 including a resilient member located between the moveableportion and the wall of the head portion.
 17. The headrest assembly asrecited in claim 16 wherein the resilient member is a coil spring. 18.The headrest assembly as recited in claim 16 wherein the resilientmember biases the moveable portion to the first position, and manualpressure moves the moveable portion to the second position against thebias of the resilient member.
 19. The headrest assembly as recited inclaim 13 wherein the feature that engages one of the notches of the postis a metal piece.
 20. The headrest assembly as recited in claim 19wherein the metal piece is molded into the moveable portion or snap fitinto an opening in the moveable portion.